Charles eudolph steigee



0. R. STEI'GIER & J. W. KERR. G rushing and'Grinding Pan for Reducing Ores.

No. 237,921. Patented. Feb. 15,1881.

. UNITED STATES l ATENT @FFICE.

CHARLES B. STEIGER AND JAMES W. KERR, OF SAN FRANCISCO, CAL.

CRUSHING AND GRINDING PAN FOR REDUCING ORES.

SPECIFICATION forming part of Letters Patent No. 237,921, dated February 15, 1881.

' Application filed January 21, 1880.

Our invention relates tocertain improve,

ments in the reduction of ores, and in the apparatus employed for that purpose; and it consists in the combination, with what is known as the Muller orHepburn pan, of ascreen or screens, which are fitted into the side of the pan and provided with controlling-gates, so that the pan may be operated continuously, as

may be desired.

lteferrin g to the accompanying drawings for a more complete explanation of our invention, Figure 1 is a view of ourimproved pan. Fig. 2 is a section of the same.

A is the body of the pan, and B is the bottom, which is made conical or dish-shaped, as shown, and provided with suitable draw-01f pipes or openings, C.

Within the pan are fitted peculiarly-shaped dies D, and a muller, E, is driven so as to revolve above these dies by means of a yoke, a, or other connection from the vertical drivingshaft F, which passes up through the center of the pan, as shown. The muller has grooves formed on its lower surface corresponding with those in the dies, and it is suspended by its yoke so as to turn out of contact with the dies, so that its motion, in conjunction with the grooves in its lower face and those in the dies, causes a constant circulation of the pulp beneath the muller up at the outside of the pan, and thence to the center, where it again passes down beneath the muller.

Upon the upper surface of the muller are a series of rollers, G, which are so formed that their peripheries will roll against the inclined side of the bottom B, and they are caused to roll by the motion of the muller.

Into this class of pans the ore is fed from the rock-breaker, and is pulverized by the action of the rollers, as before described but the operation has hitherto been conducted by placing successive charges in the pan, and when sufficiently reduced the pulp is drawn offinto the amalganiating-pans. One objection to this is the intermittent nature of the operation and the time lost in charging and drawing off, and another is, that much of the pulp is reground after it has become fine enough and is converted into slime, which will not readily amalgamate. v

In our invention we form the side A of the pan with one or more openings, H, over which a screen, I, is secured, having a mesh of the proper fineness to permit the escape of all the material as soon as it is sufficiently reduced. Y

J is a spout or trough, which directs the material into the amalgamating-pans or other receptacles after it has passed through the screen.

In working with our improved pan, the ore is fed continuously into the pan, and as fast as it will pass through the screen it is discharged, so that there need be no intermission in the work, and the screens are not as rapidly worn out, because the ore is not thrown forcibly against them, as it is by the falling of the stamp and the splash in the battery.

If desired, amalgamation may also be carried on within the pan.

A sliding gate, K, is fitted over the opening H, and this may be closed down at any time, so as to prevent the escape of any pulp. When this-is done the pan will work separate charges, like ordinary pans, and the ore may then be ground for about three hours, after which the quicksilver is introduced and the amalgamation completed.

By the use of our improved pan we are enabled to work the ore much more perfectly and rapidly, as every particle of ore passes out through the screen as soon as it is reduced to the proper size, and the formation of slimes is prevented, so that the amalgamation will be more perfect.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is-

The combination, with the pan A, provided with a rotating muller, a series of dies, D In witness whereof We have hereunto set and grinding-rollers G, and an opening, H, in our hands. its side, of the screen I, secured in said open- CHARLES RUDOLPH STEIGER.

ing, and adjustable sliding gate K, whereby JAMES WATT KER-R. 5 the ore may be fed continuously into the pan Vitnesses:

and continuously discharged therefrom or re- XVILLIAM HARNEY,

mined in the pan, substantially as described. FRANK A. BROOKS. 

